Answer:
u meant the answer to this ques
Explanation:
22
×12
------
44
22 ×
----------
264
-----------
or the answer can be 22×12=264
B.Elements
Explanation: they cannot be separated
Methane is the compound CH4, and burning it uses the reaction:
CH4 + O2 -> CO2 + H2O, which is rather exothermic. To find the heat released by burning a certain amount of the substance, you should look at the bond enthalpy of each compound, and then compare the values before and after the reaction. In methane, there are 4 C-H bonds, which have bond energy of 416 kj/mol, resulting in a total bond energy of 1664 kj/mol. O2 is 494 kj/mol. Therefore we have a total of 2080 kj/mol on the left side. On the right side we have CO2, which has 2 C=O bonds, each at 799 kj/mol each, resulting in 1598 kj/mol, and H2O has 2 O-H bonds, at 459kj/mol each, resulting in a total of 2516 kj/mol on the right hand side. Now, this may be confusing because the left hand side seems to have less heat than the right, but you just need to remember: making minus breaking, which results in a total change of 436kj/mol heat evolved.
Now it is a simple matter of find the mols of CH4 reacted, using n=m/mr.
n = 9.5/16.042 = 0.592195 mol
Therefore, if we reacted 0.592195 mol, and we produced 436 kj for one mol, the total amount of energy evolved was 436*<span>0.592195 kj, or 258.197 kj.</span>
The questions tha science can answer are those can be tested to try to find a definite answer.
For example, whether light is wave or particle is matter of science.
Questions that cannot have a definite answer are the field of religion or philosophy, and are out of the boundaries of science.
For example, does a criminal deserve the punishment of not seeing light? It is a moral question, which to be responded needs the intervention of philosophy and that could have different anwers at different times and in different societies.
Answer:
Phosphorus is more electronegative than hydrogen
Explanation:
Electronegativity is a measure of the tendency of an atom to attract a bonding pair of electrons towards itself thereby making a molecule to be polar. The Pauling scale is the most commonly used to measure electronegativity. Fluorine (the most electronegative element) is assigned a value of 4.0 on the Pauling's scale, and values range down to caesium and francium which are the least electronegative elements.
Electronegativity increases from left to right across the periodic table (across the period) hence, phosphorus is far more electronegative than hydrogen. Being more electronegative than hydrogen, phosphorus attracts the bonding electron pair of the P-H bond closer to itself than hydrogen. Since the electrons of the bond are closer to phosphorus than hydrogen, the phosphorus atom acquires a partial negative charge while the hydrogen atom acquires a partial positive charge.
